Treatment

Primary Treatment of Neutrophilic CCH

Antibiotic Therapy

• Should be based ideally on culture and sensitivity (Weiss et al. 1997)

• When cultures are negative or empiric selection is necessary:

î Select antibiotic effective against most enteric gram-negative aerobes and has good penetration of the liver and bile such as cephalexin, cefadroxil, amoxicillin-clavulanate, amoxicillin, or enrofloxacin

î Metronidazole can be added to extend the spectrum to anaerobes.

• Continue treatment for 4-6 weeks, even though most cats improve clinically within a week (Twedt et al. 2014)

Corticosteroid Therapy

• Considered in cats with neutrophilic CCH where liver biopsy sections contain rela­tively few neutrophils with a predominance of lymphocytes and plasma cells and where response to appropriate antibiotic therapy is poor or incomplete (Twedt et al. 2014).

• It may be difficult to ascertain if clinical improvement of these cases on corticoster­oid therapy is attributable to resolution of the liver disease or perhaps due to improve­ment of the frequently concurrent IBD or pancreatitis.

Primary Treatment of Lymphocytic CCH

Corticosteroid Therapy

• Indicated to control the inflammatory component of the disease

• Prednisolone 1-2 mg/kg PO SID initially

î Corticosteroid of choice, as it is well absorbed after oral administration in cats

• Monitor clinical signs and biochemical parameters for improvement

• Slowly taper the dose of prednisolone after 4-6 weeks if improvement is seen:

î Reduce the dosage by 50 % every two weeks until 0.5 mg/kg PO SID is reached

î If clinical and biochemical improvement is evident, a chronic dose of 0.5 mg/kg PO every second day can be adminis­tered for four weeks or long term, as needed to control clinical signs

• Treatment decisions should ideally be based on repeat liver biopsies, although this is not performed routinely in practice

• Long-term corticosteroid treatment is well tolerated by most cats, although cats should be carefully monitored for develop­ment of diabetes mellitus.

• Some anecdotal reports discuss the use of chlorambucil in conjunction with predni­solone in severe cases (Center 2009)

î Chlorambucil 4 mg/m² PO every second day

• Other types of immunosuppressive ther­apy is sometimes advised for refractory cases, but no reported studies exist and severe side effects are commonly seen (Center 2009)

î Cyclosporine: 3-5 mg/kg PO SID

î Methotrexate: 0.13 mg PO TID for 3 doses at 7-day intervals

• It should be noted that corticosteroid ther­apy may not be contraindicated in cats with concurrent chronic pancreatitis or IBD - in fact, it may actually be beneficial (Twedt et al. 2014)

Acute Supportive Treatment of all Cases of CCH

Cats with CCH are frequently acutely ill and require intensive supportive care in conjunc­tion with specific therapy.

• Intravenous fluids

î A balanced polyionic crystalloid fluid is recommended.

• Correction of electrolyte abnormalities such as hypokalemia and hypophosphatemia

• Treat coagulation abnormalities (if present) î Vitamin K₁: 0.5-1.5 mg/kg SC BID for

three injections or 5 mg PO SID

î Allow adequate response interval after initiation of Vitamin K therapy before biopsies of the liver are obtained

• Ursodeoxycholic acid: 10-15 mg/kg PO SID

î Beneficial effects include improvement of damage to cell membranes caused by retained toxic bile acids, improved bil­iary secretion of bile acids, improved bile flow (choleresis) and prevention of mito­chondrial damage. It also has antifibrotic and immunomodulatory properties (Twedt et al. 2014)

• Nutritional support

î Place a naso-esophageal feeding tube if voluntary food intake is inadequate

î Feed a high-energy, high-protein diet such as Maximum Calorie (IAMS Veterinary Formula) and Prescription Diets a/d or m/d (Hill's Pet Nutrition), as protein is extremely important for liver repair and regeneration

î Only restrict dietary protein if signs of hepatic encephalopathy are evident, and add lactulose (0.25-0.5 ml/kg TID PO) and neomycin (22 mg/kg TID PO) (Zoran 2012).

• Pain management is indicated in most cats with CCH, especially those with acute signs. Buprenorphine, hydromorphone, meperidine, or butorphanol can be used (Twedt etal. 2014). Fentanyl patch (25 pg/hr) can be used for longer-duration pain con­trol. Effective blood levels are only reached after 3-12 hours in cats, therefore concur­rent opioid administration will be needed initially.

• Control vomiting

î Maropitant: 1 mg/kg SID IV, SC or PO is the drug of choice, however, as maropi- tant is metabolized by the liver a dosage of 0.5mg/kg is sometimes used in cases with advanced hepatic dysfunction (Zoran 2012)

î Ondansetron (0.1-1 mg/kg SID-BID IV/ PO) or dolasetron (0.5-1 mg/kg SID- BID IV/PO) is advised if vomiting persists

î Metoclopramide (0.2-0.5 mg/kg TID SC/PO) is a weak antiemetic in cats, but is commonly used for its prokinetic effects (Twedt et al. 2014)

• Surgery

î Surgical therapy is uncommon, but may be required in some cases for gallbladder rupture, cholelith removal, or bile duct decompression if biliary obstruction is present (Weiss et al. 1997)